Crossover for RCA transistor

[donegone]

I have an old transistor amplifier with no make or model so this is proving to be difficult. The output devices are shorted. Written on the device is: RCA 36947 WC M 6D. Can anyone provide me with a crossover and/or information on how to determine what the component is? Thank you in advance.

[52 Bill]

This will be a tough one. That number is probably a house number that will not mean anything to anyone other than the original manufacturer.

First off what style case is it? Are there any more of them in the amp that are not shorted? How does the device wire up to the power supply? What are the ratings of the power supply? Voltage, pos only or pos and neg, etc.

[Steve Conner]

Yep, figure out if they are NPN, PNP, germanium or silicon. If they're germanium throw the amp away. If silicon, the MJ15024 is recommended as a good replacement for any NPN TO-3, and the MJ15025 for PNP.

These work in practically any circuit, except for some really old designs where they oscillate, because they have far more bandwidth than the circuit was designed for. In this case, try the 2N3055, voltage ratings permitting. (Many of those house-numbered transistors were just specially selected 2N3055s.)

[JHow]

...If they're germanium throw the amp away. ...

I see your emoticon, so I know you are laughing, but there might be some hope for germanium. With R.G. Keen's advice at geofex.com I was able to replace the germanium outputs with silicon by fixing the bias string on my ancient Vox solid state.